Type
Zone
Age range
463.7–462.4 Ma
Middle Ordovician
Darriwilian
Cahabagnathus friendsvillensis
Phragmodus polonicus
Histiodella holodentata
463.7463.6463.5463.4463.3463.2463.1463.0462.9462.8462.7462.6462.5462.4